A tinker, or member of the Irish travlelling community. See also the British pikey. They live in caravans in random fields and leave the place generally in a mess. However there are some good travellers who are given a hard time and a bad name due to the bad ones.
See also the less polite term: knacker

1. British term used to refer collectively to two separate traditionally-nomadic groups found in the UK: Irish Travellers (also known as Pavee, tinkers and pikeys) and Romani (also known as Roma, Romany, Romanichals, Romnichals and Kale). The term is used to replace the traditional term "gypsy", which is now considered offensive by some. The term refers to members of these two groups regardless of whether they actually live a nomadic or sedentary lifestyle.

2. A term used by people who are travelling away from home, but have distaste for the terms "tourist" and "holidaymaker". Travellers are often said to be distinct from tourists/holidaymakers due to the fact that they travel for longer periods of time, seeing a variety of places in one trip, and make an effort to experience the real spirit of the places they visit, rather than just tourist resorts. Those who self-describe as travellers are also often travelling on a tighter budget than traditional tourists, staying in hostels rather than hotels. A roughly synonymous term is "backpacker".

1. Although the Romani and the Irish Travellers have very different histories and cultures, the majority of the British population are unaware of existence of two distinct groups, and consider both to be "gypsies" or "travellers".

2. The great thing about staying in hostels is the opportunity to meet and hang out with other travellers, from all over the world.